Deep-drawn tray, in particular aluminum tray

ABSTRACT

A deep-drawn tray, in particular an aluminum tray, having a rolled edge and an encircling sealing face, by means of which it can be sealed to a plate. In order to provide readily visible markings or to improve the appearance, the rolled edge of the tray is provided with a lacquer.

The invention relates to a deep-drawn tray, in particular an aluminum tray, having a rolled edge corresponding substantially to EP 2 334 564 and the preamble of claim 1.

The cited document discloses the production of a tray made of aluminum, in particular for food or beverage ingredients but also for animal food, with a rolled edge in which the inside and outside are colored differently, on the one hand to allow for a visually appealing appearance after sealing a plate onto it, on the other hand to provide, by appropriate combination of the interior color and the exterior color, wherein the former is also visible on the roll edge from the outside, to the user joy and/or information about the contents of the still closed shell or other information by means of the visually pleasing impression.

The steps in the cited document for the production of such a container fulfill their purpose but are insofar disadvantageous as that consumers do not appreciate various colors in association with a food, animal food, beverage ingredients, etc., such as green or yellow; however, according to the content, other colors may also be undesirable. Furthermore, the previously known method does not allow for the provision of more detailed information; it is merely possible to combine the barely variable exterior color with an interior color to be selected from only a small group of colors.

From DE 87 09 640 U, which relates to the stiffening of containers made of aluminum, it is well known that the surface is laminated with a plastic film or coated with a heat-sealable lacquer.

The application of sealable lacquer on an aluminum tray is also disclosed in DE 690 28 628 T2, the translation of EP 468 079.

There is thus a desire for a greater choice over the former document, and there is also a desire to be able to determine and display the visual appearance of more diverse and communicable information within wide limits and independent of the raw material of the tray and its contents.

It is the object of the invention to provide a solution for this problem.

According to the invention, this is done by the features specified in the characterizing part of claim 1, in other words, that during imprinting of the tray which on its bottom surface, the outer surface, receives an imprint of information and/or a decorative motif, in the area of its rolled edge is provided on the later inside and/or the later outside with a colored lacquer overprint, which optionally also extends into the region of the sealing face and/or the sealing surface opposite to the outer surface.

The aluminum trays for the intended use are imprinted on the outside prior to the deep draw process and, either during printing or independently of printing prior to printing, markers which can be of various types, which effect the placement of the deep draw tool and of the stamping tool, are applied to the web. Therefore, during the printing process, it will pose not problem to apply, precisely matching these markings on the desired side of the continuous material, be it the later inside and/or the later outside, printing material exclusively in the area of the later rolled edge, optionally also extending into the region of the sealing face and/or the sealing surface opposite to the outer surface. Since this is a printing process, preferably a gravure printing process, it is easily possible to apply various colors, which thus enable correct color coding or visually appealing running colors (rainbow, etc.).

The accuracy of the color application is to be kept, without much adjustment, in such close geometric tolerances that, if so desired, the actual sealing face of the plate which lies within the rolled edge and/or the surface opposite to this area may be kept free of the lacquer application, so that any sealing properties of the lacquer would in this case not need to be considered.

Through application according to the invention of the lacquer only in the region of the rolled edge the user may continue to be assured of the appearance of the interior of the tray familiar to and appreciated by him, especially when the tray comes in contact with the food, the animal food, or the beverage additives, and the consumer's negative assessments known from the prior art have no basis.

The invention is explained in more detail below with reference to the drawing.

FIG. 1 shows a perspective top view of the underside of an “upside down” tray according to the invention;

FIG. 2 shows a top view of the empty tray in a perspective view from a viewpoint similar to that of FIG. 1;

FIG. 3 shows a section in the region of the rolled edge in a purely schematic fashion and highly magnifies;

FIG. 4 shows a variant of the minor figure of FIG. 1 with indicated multi-colored coding; and

FIG. 5 shows a view in accordance with FIG. 2 with an additional lacquer application on the sealing face.

Shown in FIG. 1 is an example of a deep-drawn aluminum tray 1 usually with an imprint on the bottom and optionally on the slanted side walls 3, as well as on the stiffening ribs within side wall 3 and on the colored rolled edge 4, the imprints for the most part not shown in the figure. Coloring 5 is indicated by the dots only in the minor character depicted in a larger scale.

The exterior color of tray 1 may be uncolored aluminum, it may be a lacquer or plastic coating, optionally mostly yellow or golden, or any other design desired by the manufacturer, the filler, or the consumer. It is vital and evidently shown in the figure that the rolled portion of the rolled edge 4 on the inside 2 of the aluminum foil from which the tray was deep-drawn is colored, so that the color becomes visible from the outside during rolling, both from below (FIG. 1) as well as seen from above (FIG. 2).

The rolled edge is shown “neutral” in FIG. 3, because while in most cases it is rolled in such a manner that the inside of the foil is rolled outwards, there are also applications in which the outside is rolled inward. Most of time, the roll is situated completely or substantially below or above the sealing face 6, and rarely, as shown, in a centered manner. Through this neutral depiction, FIG. 3 is intended to indicate all these possibilities. Depending on the intended rolling direction, the ink application should be carried out on the “right” side, which is not a problem with the commonly available printing presses.

FIG. 2 shows the variant in which the coloring covers only the area of the rolled edge but not, or hardly, the shoulder 6 of the tray on which the sealing with the plate (not shown) takes place. Since in almost all applications the inside of an aluminum tray is coated with a sealable plastic layer, such as to preserve the content from direct contact with the aluminum, this solution still provides the entire or almost entire shoulder surface extending in form of a ring around the opening of the tray for sealing with the plate.

FIG. 5 shows a variant in which the lacquer also covers the sealing face 6; it may either be itself sealable or shine through from under the then preferred transparent sealing layer. The variant in which the opposite surface 7 (FIG. 1) facing sealing face 6 is imprinted is not shown.

Finally, it can be seen from FIG. 3 that the ink or lacquer applied in the course of the imprinting of the continuous material if so desired actually only covers the region flanged to the rolled edge later during deep drawing and thus fulfills its purpose in a visually appealing and technologically meaningful manner.

Irrespective of the imprinting of the rolled edge, it is of course possible, as already known from the prior art, to independently of one another imprint the inside and/or the outside of the tray away from the rolled edge. Since printing processes may be carried out very accurately, the boundary to the printed rolled edge may be maintained very accurately.

The term “paint” or “lacquer” is to be understood in the broadest sense and includes all materials that can be applied by a printing process. The change in color, brightness, intensity along the roll edge may be due to purely aesthetic reasons but may also encode information as is known mutatis mutandis from the bar code and other identification features.

Markers may be printed onto the continuous material; they may also consist of imprints of continuous material, and they may consist of “multiple parts” per later tray, for example, to specify the correct angular position in respect to the deep draw mold and the like, as provided for in the prior art.

The individual variants of the invention may be combined in any way. Even though the focus of the invention may specify an aluminum foil as starting material, it is nevertheless possible to form in accordance with the invention other deep drawable starting materials. The usable colors will be readily apparent to those of ordinary skill in the packaging arts, knowing the invention and application, and will most likely be those already used in the art of printing such trays.

REFERENCE

1. Tray

2. Inside

3. Outside

4. Rolled Edge

5. Lacquer, Color

6. Sealing Face, Shoulder

7. Opposite Surface 

1-4. (canceled)
 5. A deep-drawn tray having a rolled edge and an encircling sealing face, where the deep drawn tray is capable of being sealed to a plate via the encircling sealing face, further comprising a lacquer provided on the rolled edge.
 6. The deep-drawn tray of claim 5, where the deep-drawn tray is an aluminum tray
 7. The deep-drawn tray of claim 5, wherein the lacquer is also provided on at least one of the encircling sealing face and the opposite surface of the deep-drawn tray.
 8. The deep-drawn tray of claim 5, wherein one or more of the color, brightness, and intensity of the lacquer along the rolled edge changes.
 9. A method for producing a tray made of a continuous material, the tray having a rolled edge and an encircling sealing face and being capable of being sealed to a plate via the encircling sealing face, and further comprising a colored lacquer overprint provided on the rolled edge, the method comprising: a. applying a marking to the continuous material; b. punching out a tray material from the continuous material based upon a position of the applied marking; and c. deep-drawing the tray material to form the desired tray based upon the position of the applied marking; wherein the method further comprises applying the colored lacquer overprint to the continuous material in an area that will be an inside and/or outside of the rolled edge, or applying the colored lacquer overprint to the tray material in an area that is an inside and/or outside of the rolled edge.
 10. The method of claim 9, further comprising printing the continuous material prior to punching out the tray material.
 11. The method of claim 9, wherein applying the marker to the continuous material occurs before or optionally during printing the continuous material.
 12. The method of claim 10, wherein applying the colored lacquer overprint occurs before, during, or after printing the continuous material.
 13. The method of claim 9, wherein applying the colored lacquer overprint includes extending the colored lacquer overprint into a region of the sealing face and/or a sealing surface disposed opposite to an outer surface of the tray. 